1 /* SPDX-License-Identifier: GPL-2.0-or-later */
3 * iSCSI lib definitions
5 * Copyright (C) 2006 Red Hat, Inc. All rights reserved.
6 * Copyright (C) 2004 - 2006 Mike Christie
7 * Copyright (C) 2004 - 2005 Dmitry Yusupov
8 * Copyright (C) 2004 - 2005 Alex Aizman
13 #include <linux/types.h>
14 #include <linux/wait.h>
15 #include <linux/mutex.h>
16 #include <linux/timer.h>
17 #include <linux/workqueue.h>
18 #include <linux/kfifo.h>
19 #include <linux/refcount.h>
20 #include <scsi/iscsi_proto.h>
21 #include <scsi/iscsi_if.h>
22 #include <scsi/scsi_transport_iscsi.h>
24 struct scsi_transport_template;
25 struct scsi_host_template;
31 struct iscsi_transport;
32 struct iscsi_cls_session;
33 struct iscsi_cls_conn;
38 #define ISCSI_DEF_XMIT_CMDS_MAX 128 /* must be power of 2 */
39 #define ISCSI_MGMT_CMDS_MAX 15
41 #define ISCSI_DEF_CMD_PER_LUN 32
43 /* Task Mgmt states */
55 /* Connection flags */
56 #define ISCSI_CONN_FLAG_SUSPEND_TX 0
57 #define ISCSI_CONN_FLAG_SUSPEND_RX 1
58 #define ISCSI_CONN_FLAG_BOUND 2
60 #define ISCSI_ITT_MASK 0x1fff
61 #define ISCSI_TOTAL_CMDS_MAX 4096
62 /* this must be a power of two greater than ISCSI_MGMT_CMDS_MAX */
63 #define ISCSI_TOTAL_CMDS_MIN 16
64 #define ISCSI_AGE_SHIFT 28
65 #define ISCSI_AGE_MASK 0xf
67 #define ISCSI_ADDRESS_BUF_LEN 64
70 /* this is the maximum possible storage for AHSs */
71 ISCSI_MAX_AHS_SIZE = sizeof(struct iscsi_ecdb_ahdr) +
72 sizeof(struct iscsi_rlength_ahdr),
73 ISCSI_DIGEST_SIZE = sizeof(__u32),
82 ISCSI_TASK_ABRT_TMF, /* aborted due to TMF */
83 ISCSI_TASK_ABRT_SESS_RECOV, /* aborted due to session recovery */
84 ISCSI_TASK_REQUEUE_SCSIQ, /* qcmd requeueing to scsi-ml */
87 struct iscsi_r2t_info {
88 __be32 ttt; /* copied from R2T */
89 __be32 exp_statsn; /* copied from R2T */
90 uint32_t data_length; /* copied from R2T */
91 uint32_t data_offset; /* copied from R2T */
92 int data_count; /* DATA-Out payload progress */
94 /* LLDs should set/update these values */
95 int sent; /* R2T sequence progress */
100 * Because LLDs allocate their hdr differently, this is a pointer
101 * and length to that storage. It must be setup at session
104 struct iscsi_hdr *hdr;
105 unsigned short hdr_max;
106 unsigned short hdr_len; /* accumulated size of hdr used */
107 /* copied values in case we need to send tmfs */
112 int itt; /* this ITT */
114 unsigned imm_count; /* imm-data (bytes) */
115 /* offset in unsolicited stream (bytes); */
116 struct iscsi_r2t_info unsol_r2t;
117 char *data; /* mgmt payload */
119 struct scsi_cmnd *sc; /* associated SCSI cmd*/
120 struct iscsi_conn *conn; /* used connection */
122 /* data processing tracking */
123 unsigned long last_xfer;
124 unsigned long last_timeout;
125 bool have_checked_conn;
127 /* T10 protection information */
130 /* state set/tested under session->lock */
133 struct list_head running; /* running cmd list */
134 void *dd_data; /* driver/transport data */
137 /* invalid scsi_task pointer */
138 #define INVALID_SCSI_TASK (struct iscsi_task *)-1l
140 static inline int iscsi_task_has_unsol_data(struct iscsi_task *task)
142 return task->unsol_r2t.data_length > task->unsol_r2t.sent;
145 static inline void* iscsi_next_hdr(struct iscsi_task *task)
147 return (void*)task->hdr + task->hdr_len;
150 static inline bool iscsi_task_is_completed(struct iscsi_task *task)
152 return task->state == ISCSI_TASK_COMPLETED ||
153 task->state == ISCSI_TASK_ABRT_TMF ||
154 task->state == ISCSI_TASK_ABRT_SESS_RECOV;
157 /* Connection's states */
159 ISCSI_CONN_INITIAL_STAGE,
162 ISCSI_CONN_CLEANUP_WAIT,
166 struct iscsi_cls_conn *cls_conn; /* ptr to class connection */
167 void *dd_data; /* iscsi_transport data */
168 struct iscsi_session *session; /* parent session */
170 * conn_stop() flag: stop to recover, stop to terminate
173 struct timer_list transport_timer;
174 unsigned long last_recv;
175 unsigned long last_ping;
178 struct iscsi_task *ping_task;
180 /* iSCSI connection-wide sequencing */
186 int c_stage; /* connection state */
188 * Preallocated buffer for pdus that have data but do not
189 * originate from scsi-ml. We never have two pdus using the
190 * buffer at the same time. It is only allocated to
191 * the default max recv size because the pdus we support
192 * should always fit in this buffer
195 struct iscsi_task *login_task; /* mtask used for login/text */
196 struct iscsi_task *task; /* xmit task in progress */
199 /* items must be added/deleted under frwd lock */
200 struct list_head mgmtqueue; /* mgmt (control) xmit queue */
201 struct list_head cmdqueue; /* data-path cmd queue */
202 struct list_head requeue; /* tasks needing another run */
203 struct work_struct xmitwork; /* per-conn. xmit workqueue */
204 unsigned long flags; /* ISCSI_CONN_FLAGs */
206 /* negotiated params */
207 unsigned max_recv_dlength; /* initiator_max_recv_dsl*/
208 unsigned max_xmit_dlength; /* target_max_recv_dsl */
213 /* values userspace uses to id a conn */
215 char *persistent_address;
217 unsigned max_segment_size;
218 unsigned tcp_xmit_wsf;
219 unsigned tcp_recv_wsf;
220 uint16_t keepalive_tmo;
222 uint8_t tcp_timestamp_stat;
223 uint8_t tcp_nagle_disable;
224 uint8_t tcp_wsf_disable;
225 uint8_t tcp_timer_scale;
226 uint8_t tcp_timestamp_en;
227 uint8_t fragment_disable;
229 uint8_t ipv6_traffic_class;
230 uint8_t ipv6_flow_label;
231 uint8_t is_fw_assigned_ipv6;
235 uint64_t txdata_octets;
236 uint64_t rxdata_octets;
237 uint32_t scsicmd_pdus_cnt;
238 uint32_t dataout_pdus_cnt;
239 uint32_t scsirsp_pdus_cnt;
240 uint32_t datain_pdus_cnt;
241 uint32_t r2t_pdus_cnt;
242 uint32_t tmfcmd_pdus_cnt;
243 int32_t tmfrsp_pdus_cnt;
245 /* custom statistics */
246 uint32_t eh_abort_cnt;
247 uint32_t fmr_unalign_cnt;
251 struct kfifo queue; /* FIFO Queue */
252 void **pool; /* Pool of elements */
253 int max; /* Max number of elements */
256 /* Session's states */
258 ISCSI_STATE_FREE = 1,
259 ISCSI_STATE_LOGGED_IN,
261 ISCSI_STATE_TERMINATE,
262 ISCSI_STATE_IN_RECOVERY,
263 ISCSI_STATE_RECOVERY_FAILED,
264 ISCSI_STATE_LOGGING_OUT,
267 struct iscsi_session {
268 struct iscsi_cls_session *cls_session;
270 * Syncs up the scsi eh thread with the iscsi eh thread when sending
271 * task management functions. This must be taken before the session
274 struct mutex eh_mutex;
276 wait_queue_head_t ehwait; /* used in eh_abort() */
277 struct iscsi_tm tmhdr;
278 struct timer_list tmf_timer;
279 int tmf_state; /* see TMF_INITIAL, etc.*/
280 struct iscsi_task *running_aborted_task;
282 /* iSCSI session-wide sequencing */
287 /* This tracks the reqs queued into the initiator */
288 uint32_t queued_cmdsn;
292 int lu_reset_timeout;
293 int tgt_reset_timeout;
295 unsigned short max_r2t;
297 unsigned first_burst;
302 int dataseq_inorder_en;
318 char *discovery_parent_type;
319 uint16_t discovery_parent_idx;
320 uint16_t def_taskmgmt_tmo;
322 uint8_t auto_snd_tgt_disable;
323 uint8_t discovery_sess;
324 uint8_t chap_auth_en;
325 uint8_t discovery_logout_en;
326 uint8_t bidi_chap_en;
327 uint8_t discovery_auth_optional;
328 uint8_t isid[ISID_SIZE];
331 struct iscsi_transport *tt;
332 struct Scsi_Host *host;
333 struct iscsi_conn *leadconn; /* leading connection */
334 /* Between the forward and the backward locks exists a strict locking
335 * hierarchy. The mutual exclusion zone protected by the forward lock
336 * can enclose the mutual exclusion zone protected by the backward lock
337 * but not vice versa.
339 spinlock_t frwd_lock; /* protects session state, *
340 * cmdsn, queued_cmdsn *
341 * session resources: *
342 * - cmdpool kfifo_out , *
343 * - mgmtpool, queues */
344 spinlock_t back_lock; /* protects cmdsn_exp *
346 * cmdpool kfifo_in */
347 int state; /* session state */
348 int age; /* counts session re-opens */
350 int scsi_cmds_max; /* max scsi commands */
351 int cmds_max; /* size of cmds array */
352 struct iscsi_task **cmds; /* Original Cmds arr */
353 struct iscsi_pool cmdpool; /* PDU's pool */
354 void *dd_data; /* LLD private data */
364 /* hw address or netdev iscsi connection is bound to */
368 wait_queue_head_t session_removal_wq;
369 /* protects sessions and state */
374 struct workqueue_struct *workq;
381 extern int iscsi_eh_abort(struct scsi_cmnd *sc);
382 extern int iscsi_eh_recover_target(struct scsi_cmnd *sc);
383 extern int iscsi_eh_session_reset(struct scsi_cmnd *sc);
384 extern int iscsi_eh_device_reset(struct scsi_cmnd *sc);
385 extern int iscsi_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *sc);
386 extern enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *sc);
389 * iSCSI host helpers.
391 #define iscsi_host_priv(_shost) \
392 (shost_priv(_shost) + sizeof(struct iscsi_host))
394 extern int iscsi_host_set_param(struct Scsi_Host *shost,
395 enum iscsi_host_param param, char *buf,
397 extern int iscsi_host_get_param(struct Scsi_Host *shost,
398 enum iscsi_host_param param, char *buf);
399 extern int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev);
400 extern struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
402 bool xmit_can_sleep);
403 extern void iscsi_host_remove(struct Scsi_Host *shost);
404 extern void iscsi_host_free(struct Scsi_Host *shost);
405 extern int iscsi_target_alloc(struct scsi_target *starget);
406 extern int iscsi_host_get_max_scsi_cmds(struct Scsi_Host *shost,
407 uint16_t requested_cmds_max);
412 extern struct iscsi_cls_session *
413 iscsi_session_setup(struct iscsi_transport *, struct Scsi_Host *shost,
414 uint16_t, int, int, uint32_t, unsigned int);
415 extern void iscsi_session_teardown(struct iscsi_cls_session *);
416 extern void iscsi_session_recovery_timedout(struct iscsi_cls_session *);
417 extern int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
418 enum iscsi_param param, char *buf, int buflen);
419 extern int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
420 enum iscsi_param param, char *buf);
422 #define iscsi_session_printk(prefix, _sess, fmt, a...) \
423 iscsi_cls_session_printk(prefix, _sess->cls_session, fmt, ##a)
426 * connection management
428 extern struct iscsi_cls_conn *iscsi_conn_setup(struct iscsi_cls_session *,
430 extern void iscsi_conn_teardown(struct iscsi_cls_conn *);
431 extern int iscsi_conn_start(struct iscsi_cls_conn *);
432 extern void iscsi_conn_stop(struct iscsi_cls_conn *, int);
433 extern int iscsi_conn_bind(struct iscsi_cls_session *, struct iscsi_cls_conn *,
435 extern void iscsi_conn_unbind(struct iscsi_cls_conn *cls_conn, bool is_active);
436 extern void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err);
437 extern void iscsi_session_failure(struct iscsi_session *session,
439 extern int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
440 enum iscsi_param param, char *buf);
441 extern int iscsi_conn_get_addr_param(struct sockaddr_storage *addr,
442 enum iscsi_param param, char *buf);
443 extern void iscsi_suspend_tx(struct iscsi_conn *conn);
444 extern void iscsi_suspend_queue(struct iscsi_conn *conn);
445 extern void iscsi_conn_queue_work(struct iscsi_conn *conn);
447 #define iscsi_conn_printk(prefix, _c, fmt, a...) \
448 iscsi_cls_conn_printk(prefix, ((struct iscsi_conn *)_c)->cls_conn, \
452 * pdu and task processing
454 extern void iscsi_update_cmdsn(struct iscsi_session *, struct iscsi_nopin *);
455 extern void iscsi_prep_data_out_pdu(struct iscsi_task *task,
456 struct iscsi_r2t_info *r2t,
457 struct iscsi_data *hdr);
458 extern int iscsi_conn_send_pdu(struct iscsi_cls_conn *, struct iscsi_hdr *,
460 extern int iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
462 extern int __iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
464 extern int iscsi_verify_itt(struct iscsi_conn *, itt_t);
465 extern struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *, itt_t);
466 extern struct iscsi_task *iscsi_itt_to_task(struct iscsi_conn *, itt_t);
467 extern void iscsi_requeue_task(struct iscsi_task *task);
468 extern void iscsi_put_task(struct iscsi_task *task);
469 extern void __iscsi_put_task(struct iscsi_task *task);
470 extern void __iscsi_get_task(struct iscsi_task *task);
471 extern void iscsi_complete_scsi_task(struct iscsi_task *task,
472 uint32_t exp_cmdsn, uint32_t max_cmdsn);
477 extern void iscsi_pool_free(struct iscsi_pool *);
478 extern int iscsi_pool_init(struct iscsi_pool *, int, void ***, int);
479 extern int iscsi_switch_str_param(char **, char *);
482 * inline functions to deal with padding.
484 static inline unsigned int
485 iscsi_padded(unsigned int len)
487 return (len + ISCSI_PAD_LEN - 1) & ~(ISCSI_PAD_LEN - 1);
490 static inline unsigned int
491 iscsi_padding(unsigned int len)
493 len &= (ISCSI_PAD_LEN - 1);
495 len = ISCSI_PAD_LEN - len;